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10

You describe "a whistle sound when air is pushed through a tight space". That is a familiar phenomenon. Essentially, you hear a self-sustaining resonance - something is driving the air mass in a way that causes a resonance that becomes a recognizable pitch. When air flows rapidly around a tight opening / sharp lip, you get flow with a very high Reynolds ...


4

Acoustic waves travel through a medium (air, water, metal, etc), there is no known medium through which light travels. Both the speed of sound1 and the speed of light have fixed values regardless of the speed of their source. Acoustic waves can be longitudinal (in gases) or transversal (in solids) whereas light is only transversal. You can measure acoustic ...


3

It is not amplification! The purpose of the guitar body is to impedance and mode match between the string and the surrounding air. Intuition When a an object vibrates it pushes on the surrounding air creating pressure waves which we hear as sound. A string vibrating alone without the body of the instrument doesn't make a very loud sound because exchange of ...


2

The beat frequency is very simply: $$f_{beat}=|f_1-f_2|$$ So there is no limit on how far apart they can be. In demonstrating the beat frequency one frequently uses frequencies that are slightly apart because it produces the typical "beating." If for example you were using the frequencies $561.6$ Hz and $300$ Hz you would get a resulting frequency of ...


2

By superposition principle we will arrive at, $$y_{total} = {[ 2Acos(2\pi \Delta f/2) ]cos(2\pi f_{av})} $$ The term inside the [] brackets can be considered as the slowly varying function that modulates the carrier wave with frequency $f_{av}$. (It is indeed an example of amplitude modulation or AM.) This function--the modulation of the amplitude--is the ...


2

For practical purposes, we can assume that the disappearance of a 1.2 cubic cm (1.2 ml) object gives a waveform that's very similar to the sudden appearance of a 1.2 ml object, except for the sign of the resulting pressure wave. Now we do have a simple means to create that effect: setting off gunpowder will suddenly produce a lot of gas. You'd need just a ...


2

For general audio programming or playback, 96kHz or 192hHz is simply useless. Indeed, the Nyquist theorem tells you that a signal can be exactly reproduced given that the sample rate is greater than the highest frequency contained in the original signal. The "excuse" of the slope of analog filter required after digital to analog conversion is no longer ...


2

As a physics & music major I've thought about this a lot. Our visible light range doesn't even cover one octave (400nm - 700nm), but you can see how 400nm light (violet) almost completes the octave from 700nm light (red). Perhaps if we could see 350nm light we'd perceive it similarly to red? I think there's an evolutionary advantage to our eyes not ...


1

Acoustic Wave is a wave in which motion of one atom causes motion of another atom because it is lying next to it. Light is change in electric or magnetic field which further causes changing fields.


1

You need to measure the sound level in decibels. This is a logarithmic scale where zero decibels corresponds to a root mean square pressure of 20 micropascals, and every 20 decibels corresponds to a tenfold increase in the pressure. Once you have measured the sound level and calculated the pressure you can use the equation for the particle velocity: $$ v = ...


1

Sadly, there is no relation. While at least some chords have a nice physical basis - octaves are literally harmonics of each other - human perception of color has very little connection to the physics of light. Color is cyclical: we see high-frequency blues as near low-frequency reds with mixed-frequency purples in between, so there is no equivalent of an ...


1

The usual way that this phenomenon is described is when you hold a sea shell up to your ear, you can hear the sea What actually happens, according to this link, is that the vessel acts as a resonator / reflector for ambient noise - sounds that already present in the environment are amplified and stand out more. The "you hear your blood" myth is just ...


1

because the higher the sampling rate is the sloppier the (annalogue) filtering preceding the sampler can be to reduce the aliased noise/interference


1

When a mass-spring system moves, kinetic energy is 'stored' as momentum in the moving mass which is then converted to potential energy in the compression of a spring and back to kinetic energy as the spring extends, moving the mass back again. This periodic conversion of energy from kinetic to potential and back again is known as 'resonance' and occurs at a ...


1

Bass sound-waves are really big. The lower the bass, the bigger the wave. A single wavelength can go through a window, or door and enter back in through another window in a different room. They can go around walls and corners. They can also create resonance with large objects like walls, and this helps them to pass through because the wall is ...



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